Hi Corentin,
This is something I do quite often, so I put together a video showing how to do this sort of formatting - the specific Actual vs Forecast Months example starts from around 2.30.
Essentially you need to have another element in the view which flags the different formats you want to use (that can be text "ACT" vs "FCST" or numbers such as 1 or 0.)
Then you can apply conditional formatting to the "Actualisation" member that is based on the values/text contained in your new element.
For Conditional Formatting to work you need the element that you are basing it on to actually be part of the view... but you can "hide" that element and it still counts as being part of the view.
Thanks,
Declan
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Declan Rodger
Technical Director
Spitfire Analytics
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